ABSTRACT White-nose syndrome (WNS), an emerging fungal disease of North American bats, was first diagnosed in January 2008, although mortality and photodocumentation suggest the disease might have been present earlier. Using archived samples, we describe a definitive case of WNS in little brown bats ( Myotis lucifugus ) from New York, US, in spring 2007.

White-nose syndrome is an emerging fungal disease that has devastated hibernating bat populations across eastern North America. The causal pathogen, Pseudogymnoascus destructans (PD), is a psychrophilic fungus with a known maximal growth temperature of 20 C. Although it is widely speculated that PD is primarily spread between hibernacula by the movement of bats, experimental evidence is lacking to demonstrate that PD can endure temperatures experienced by active bats for periods of time that would facilitate dispersal of viable fungus. We used an in vitro culture-based approach to study the survival of PD conidia on three artificial growth media and bat fur. The fungus was incubated at three temperatures it might realistically be exposed to on nonhibernating bats or in the environment outside of caves and mines (24 C, 30 C, and 37 C). When incubated on artificial media, we found that PD conidia were able to survive for a maximum of 150 d when exposed to temperatures of 24 C, 60 d at 30 C, and 15 d at 37 C. At all temperatures, maximal survival duration was recorded when conidia were incubated on brain–heart infusion agar with 10% volume of sheep ( Ovis aries ) blood. When incubated on bat fur, viable PD was recovered at 180 d, 60 d, and 5 d when exposed to temperatures of 24 C, 30 C, and 37 C, respectively. Our results suggest that viable PD conidia may be able to survive on or within the bodies of bats, which may facilitate long-distance dispersal. The long-term viability of the fungus on various fomites may differ, and therefore must be assessed for each potential substrate.

Snake fungal disease (ophidiomycosis) is an emerging infection of snakes caused by Ophidiomyces ophiodiicola . Little is known about mechanisms of this pathogen's transmission and its implications for conservation of wild snake populations. We report four cases with evidence of vertical transmission of O. ophiodiicola from dam to offspring.

In 2017, we investigated a mortality event of muskrat ( Ondatra zibethicus ) in northwest Ohio, US, and determined the causes of death to be from Tyzzer's disease due to Clostridium piliforme and Klebsiella pneumoniae septicemia. The gross presentation resembled tularemia, which highlighted the importance of a complete diagnostic investigation.

ABSTRACT We describe a die-off of little brown bats ( Myotis lucifugus carissima ) associated with acute intoxication with microcystin-LR in 2016 at Scofield Reservoir in Utah, US. High levels of this cyanotoxin in water from the reservoir and gastrointestinal content of bats supported this diagnosis.

ABSTRACT We isolated Bisgaard taxon 40 from Rhinoceros Auklets ( Cerorhinca monocerata ) with pneumonia and septicemia from Washington, US, found dead in 2016. Previously isolated only from the respiratory tract of a gull (Laridae), little is known about its pathogenic potential and whether it acts as a primary or opportunistic pathogen.

ABSTRACT We documented mortality of green frog ( Rana clamitans ) tadpoles in Wisconsin, US, attributed to severe Perkinsea infection. Final diagnosis was determined by histopathology. followed by molecular detection of pathogenic Perkinsea clade (PPC) of frogs in the liver. To our knowledge, this represents the first detection of PPC in the midwestern US.

ABSTRACT We observed Sanderlings ( Calidris alba ) with facial growths in coastal Louisiana, US during summer of 2016. Severe lesions were associated with lethargy and lack of a flight response. We determined that the skin growth etiology was a bacterium of the genus Dermatophilus , rarely reported infecting birds. Sanderlings also exhibited severe amyloidosis.

Snake fungal disease (SFD) is an emerging disease of wildlife believed to be caused by Ophidiomyces ophiodiicola . Although geographic and host ranges have yet to be determined, this disease is characterized by crusty scales, superficial pustules, and subcutaneous nodules, with subsequent morbidity and mortality in some snake species. To confirm the presence of SFD and O. ophiodiicola in snakes of eastern Virginia, US, we clinically examined 30 free-ranging snakes on public lands from April to October 2014. Skin biopsy samples were collected from nine snakes that had gross lesions suggestive of SFD; seven of these biopsies were suitable for histologic interpretation, and eight were suitable for culture and PCR detection of O. ophiodiicola . Seven snakes had histologic features consistent with SFD and eight were positive for O. ophiodiicola by PCR or fungal culture.

Before the discovery of white-nose syndrome (WNS), a fungal disease caused by Pseudogymnoascus destructans , there were no reports of fungal skin infections in bats during hibernation. In 2011, bats with grossly visible fungal skin infections similar in appearance to WNS were reported from multiple sites in Wisconsin, US, a state outside the known range of P. destructans and WNS at that time. Tape impressions or swab samples were collected from affected areas of skin from bats with these fungal infections in 2012 and analyzed by microscopy, culture, or direct DNA amplification and sequencing of the fungal internal transcribed spacer region (ITS). A psychrophilic species of Trichophyton was isolated in culture, detected by direct DNA amplification and sequencing, and observed on tape impressions. Deoxyribonucleic acid indicative of the same fungus was also detected on three of five bat carcasses collected in 2011 and 2012 from Wisconsin, Indiana, and Texas, US. Superficial fungal skin infections caused by Trichophyton sp. were observed in histopathology for all three bats. Sequencing of the ITS of Trichophyton sp., along with its inability to grow at 25 C, indicated that it represented a previously unknown species, described herein as Trichophyton redellii sp. nov. Genetic diversity present within T. redellii suggests it is native to North America but that it had been overlooked before enhanced efforts to study fungi associated with bats in response to the emergence of WNS.

The emerging wildlife disease white-nose syndrome is causing widespread mortality in hibernating North American bats. White-nose syndrome occurs when the fungus Geomyces destructans infects the living skin of bats during hibernation, but links between infection and mortality are underexplored. We analyzed blood from hibernating bats and compared blood electrolyte levels to wing damage caused by the fungus. Sodium and chloride tended to decrease as wing damage increased in severity. Depletion of these electrolytes suggests that infected bats may become hypotonically dehydrated during winter. Although bats regularly arouse from hibernation to drink during winter, water available in hibernacula may not contain sufficient electrolytes to offset winter losses caused by disease. Damage to bat wings from G. destructans may cause life-threatening electrolyte imbalances.

Geomyces destructans produces the white fungal growth on the muzzle and the tacky white discoloration on wings and ears that characterize white-nose syndrome (WNS) in cave-hibernating bats. To test the hypothesis that postemergent WNS-infected bats recover from infection with G. destructans , 30 little brown bats ( Myotis lucifugus ) were collected in May 2009 from a WNS-affected hibernation site in New Jersey. All bats were confirmed to be infected with G. destructans using a noninvasive fungal tape method to identify the conidia of G. destructans and polymerase chain reaction (PCR). The bats were then held in captivity and given supportive care for 70 days. Of the 26 bats that survived and were humanely killed after 70 days, 25 showed significant improvement in the external appearance of wing membranes, had no microscopic evidence of infection by G. destructans , and had wing tissue samples that were negative for G. destructans by PCR. A subset of the bats was treated topically at the beginning of the rehabilitation study with a dilute vinegar solution, but treatment with vinegar provided no added advantage to recovery. Provision of supportive care to homeothermic bats was sufficient for full recovery from WNS. One bat at day 70 still had both gross pathology and microscopic evidence of WNS in wing membranes and was PCR-positive for G. destructans . Dense aggregates of neutrophils surrounded the hyphae that remained in the wing membrane of this bat.